The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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Wegovy Drug — What You Need to Know in the UK
Wegovy is a prescription-only weight management injection licensed in the UK and approved by the MHRA. It contains semaglutide and works as a GLP-1 receptor agonist, helping to reduce appetite and support weight loss. This guide explains NHS eligibility, how to access Wegovy through UK healthcare, and how it compares to other options. Whether you're considering NHS or private access, understanding the facts about this drug will help you make an informed decision with your GP or prescriber.
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Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
NHS Access and UK Eligibility for Wegovy
In the UK, Wegovy may be prescribed through specialist NHS weight management services (tier 3 services) for adults who meet specific criteria. You must have a BMI of 30 kg/m² or above, or a BMI of 27–29.9 with at least one weight-related health condition such as type 2 diabetes, high blood pressure, or cardiovascular disease. For people of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds apply—eligibility may start at BMI 27.5 or above due to higher health risks at lower weights.
Access via the NHS typically requires a referral from your GP to a local tier 3 weight management service. However, NHS availability is limited and varies significantly by region. Many areas have long waiting lists, sometimes lasting months or even years. The STEP clinical trials, which tested semaglutide for weight management, showed that participants lost an average of approximately 15% of their body weight over 68 weeks when using the maximum 2.4 mg dose alongside a reduced-calorie diet and increased physical activity—though individual results vary considerably.
- Eligibility: BMI 30+ or BMI 27–29.9 with comorbidities
- Access route: GP referral to tier 3 specialist service
- Waiting times: Variable by region; can be lengthy
- Clinical trial results: ~15% average weight loss at 2.4 mg dose
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS vs Private Wegovy Access in the UK
While NHS access to Wegovy offers treatment within the public health system, significant barriers exist including long waiting lists and regional availability limits. Private access is available through GPhC-registered online pharmacies without NHS referral, following an online clinical assessment by a UK-licensed prescriber. Costs typically range from £129–£250 per month depending on dose, with private access offering faster availability but at personal expense.
For NHS eligibility and costs, contact your GP or local integrated care board. Try our free GLP-1 weight loss calculator to estimate potential weight loss outcomes at different doses. Our BMI calculator can help you check whether you meet current eligibility thresholds. Whichever route you choose, Wegovy should be used alongside a reduced-calorie diet and regular physical activity for best results.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Is Wegovy available on the NHS in the UK?
Wegovy can be prescribed through NHS specialist tier 3 weight management services for eligible adults. However, availability is limited and varies by region. Many areas have significant waiting lists. Your GP can refer you to your local service, but NHS access is not assured everywhere.
What are the NHS eligibility criteria for Wegovy in the UK?
You must have a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure. For South Asian, Chinese, Black African, or Black Caribbean adults, lower thresholds apply (BMI 27.5+). Your GP or prescriber will assess your individual eligibility.
How much weight can you lose with Wegovy according to clinical trials?
The STEP-1 trial showed participants on the maximum 2.4 mg dose lost approximately 15% of their body weight over 68 weeks. This was achieved alongside a reduced-calorie diet and increased physical activity. Individual results vary significantly based on adherence and personal factors.
What's the difference between Wegovy and Ozempic in the UK?
Both contain semaglutide, but Wegovy (up to 2.4 mg) is licensed specifically for weight management. Ozempic is licensed for type 2 diabetes (up to 2 mg) and is not approved for weight loss in the UK, making off-label use inappropriate without clinical justification.
Can I get Wegovy privately if I'm not eligible for the NHS?
Yes. Private prescriptions are available through UK-licensed prescribers following an online clinical assessment. You'll need to pay for the medication directly (typically £129–£250 per month), but access is faster than many NHS waiting lists. Always ensure the prescriber is registered and legitimate.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.